1. Field of the Invention
The present invention relates to a vehicular starting and charging rotary electric machine integrating a starting motor and a charging generator.
2. Description of the Related Art
FIG. 19 is a sectional view showing a vehicular starting and charging rotary electric machine disclosed in, for example, JP-A-8-14145. In the drawing, a motor generator 1 includes a rotor 2 wound with a field winding 2a, a stator 3 wound three-phase stator winding 3a, front bracket 4 and rear bracket 5 containing the rotor 2 and stator 3, and a magnetic pole position detecting sensor 6 detecting a magnetic pole position of the rotor 2.
The rotor 2 includes a rotating shaft 9 rotatably supported by the front bracket 4 and rear bracket 5 through bearings 7, 8. An end portion of the rotating shaft 9 is projected from the front bracket 4 and a pulley 10 is fixed to a front end portion thereof. Further, other end portion of the rotating shaft 9 is projected from the rear bracket 5 and a front end portion thereof is integrated with two pieces of slip rings 11. The field wiring 2a wound around the rotor 2 is connected to a field terminal 13 fixed to the rear bracket 5 via the slip rings 11 and brushes 12.
The magnetic pole position detecting sensor 6 is coaxially installed with the rotating shaft 9 at other end portion of the rotating shaft 9 for detecting a current position of the magnetic pole of the rotating shaft 9 (rotor 2). Further, in addition to other than the magnetic pole position detecting sensor 6, an outer side of the rear bracket 5 is provided with the brushes 12 brought into sliding contact with the slip rings 11 and covered by a rear cover 14. The rear cover is fixed to the rear bracket 5 by a screw 15.
According to the vehicular starting and charging rotary electric machine according to the related art as described above, in order to interchange the brush 12, there is carried out a procedure of removing a rear cover 14 from the rear bracket 5 by detaching a screw 15, taking out the brush 12 after taking out the magnetic pole position detecting sensor 6, interchanging the brush 12 by a new one of the brush 12 and thereafter attaching the magnetic pole position detecting sensor 6 again. However, in order to promote detection accuracy, the magnetic pole position detecting sensor 6 is required high accuracy in a position of attachment relative to the magnetic pole of the rotor 2. Therefore, there is a problem that once the magnetic pole position detecting sensor 6 is detached, operation of attaching the magnetic position detecting sensor 6 again and readjusting a position of installing the magnetic pole position detecting sensor 6 is very troublesome to make operation of interchanging the brush 12 difficult.